JP5530442B2 - Back ventilation type fire wall especially for incinerator - Google Patents

Description

The back ventilation type fireproof wall according to claim 1 , comprising a boiler wall constituted by a pipe wall and a fireproof protective lining disposed with a space in front of the boiler wall. About.

  Such fire walls are used, for example, in the firebox of an incineration plant. Often the boiler wall is designed as a metal tube wall and is generally composed of tubes connected via a web. The fire-resistant protective lining, which is suspended in front of the tube wall with a space, is intended to protect the tube wall from corrosion by smoke gas. The refractory wall is also used in, for example, a fluidized bed furnace, and in the fluidized bed furnace, the boiler wall is composed of a simple metal wall having a thickness of more or less. Again, the boiler or metal wall should be protected from corrosion.

  Boiler walls and protective linings in current incineration plants are often exposed to temperatures in excess of 1000 degrees and experience expansion and contraction due to large temperature differences between individual operating conditions, even with suitable materials. The temperature difference is usually much larger in the protective lining compared to the boiler wall, which should be taken into account when selecting the material and / or designing the protective lining, The protective lining is not destroyed by greater expansion and contraction than is found in the boiler wall. Thus, the protective lining, i.e. the tiles of the protective lining, are generally not firmly attached to the boiler wall and play is allowed to some extent to move parallel to the boiler wall to offset. Given.

  Selecting the appropriate material for the protective lining allows the protective lining to conform to the boiler wall in all operating conditions. For steel boiler walls, protective linings of ceramic materials, particularly silicon carbide (SiC), have been found suitable, but the SiC content can vary greatly. In practice, SiC mixtures or SiC tiles with a SiC content of 30-90% are used.

  The tiles of the protective lining are usually sealed to each other to some extent to prevent the passage of smoke gas. In practice, however, this does not completely prevent corrosive smoke gases from penetrating the protective lining and eroding the boiler wall.

  The so-called back-ventilated wall system is advantageous for this problem. In this system, protective gas, typically air, is pumped through an intermediate space between the boiler wall and a protective lining disposed in front. The gas or air is exposed to slightly pressurized conditions compared to the firebox, and as a result, smoke gas from the firebox enters the intermediate space of the wall and erodes the boiler wall or other metal parts. It is prevented. This type of conventional wall system requires a relatively large amount of air and undesirably high pump flow.

  German Patent No. 19816059 discloses a back-ventilated fire wall comprising a pipe wall and a protective lining made of a plurality of fire-proof tiles arranged in front of the fire wall. In the wall, the intermediate space between the tube wall and the protective lining is designed as at least one closed pressure chamber, which is filled with pressurized protective gas. When the pressurization of the protective gas becomes very large, any smoke gas from the incinerator cannot enter through the protective lining. This achieves a relatively good corrosion protection effect, but the separation effect of the protective gas prevents the heat conduction between the protective lining and the tube wall, so that depending on the usage, the heat removed can be reduced. Can be inadequate.

  The present invention provides, on the one hand, that the boiler wall is reliably protected from smoke gas corrosion and, on the other hand, a protective gas that guarantees heat conduction between the protective lining optimized for the process and the boiler wall. This is based on the objective of improving the general type of fire wall in that the pump flow rate is minimized.

  This object is solved by a fire wall according to the invention as defined in the independent claim 1. Particularly advantageous further developments and configurations of the invention result from the dependent claims.

  The essence of the present invention is a fire wall as follows. The refractory wall is designed as a back ventilated system and comprises gas supply means for supplying a protective gas, typically air, in an intermediate space between the boiler wall and the protective lining. The protective gas flowing through the refractory wall prevents smoke gas from entering the wall. The gas or air is supplied through the boiler wall in the region of continuous vertical grooves provided in the tile, which can spread across the wall with minimal pressure drop. As a result, the distance between the boiler wall and the protective lining can be reduced to a few millimeters, and a relatively small amount of protective gas or air is sufficient, which in turn has the advantage that no further exhaust gas is produced. Due to the small spacing between the boiler wall and the protective lining, the heat conduction is substantially increased. The small pressure drop in the groove results in significant energy savings.

  Preferably, the grooves between the tiles adjacent in the vertical direction are arranged in a straight line and connected so as to be able to communicate with each other.

  The gas supply means preferably includes an inlet arranged in the region of the groove in the boiler wall. The inlet is preferably arranged in the lower region of the boiler wall or distributed over the entire wall of the boiler wall.

  According to a preferred exemplary embodiment, the boiler wall is a tube wall with tubes connected by a web, and the inlet is arranged in the region of the web.

  The gap width of the intermediate space is preferably 5 mm or less, and more preferably 3 mm or less.

  Preferably, the fire wall includes means for discharging the protective gas from the intermediate space and the groove. The means for venting the protective gas is advantageously provided at the top of the refractory wall and comprises an outlet through the protective lining or the boiler wall.

  According to a preferred exemplary embodiment, between the refractory tiles there are intervening tile joints that are sealed by a ceramic sealing strip of refractory material inserted and an additional grout.

  The outlet is preferably constituted by an area of the tile joint that is not sealed.

  Preferably, the tile mounting member comprises a bolt secured by the boiler wall, preferably by welding, and provided with an internal thread, a flat tile support surface, and a screw that is screwed into the bolt, respectively. The distance from the boiler wall to the tile can be changed.

  According to a preferred embodiment, the tiles of at least one horizontal tile row are arranged so that they are slightly spaced from the boiler wall compared to the remaining tiles, and as a result, the protective gas In particular, it forms a transverse path that allows air to spread across the entire width of the refractory wall.

  According to a preferred embodiment, at least some of the laterally adjacent tiles are provided with a continuous transverse path extending in a substantially horizontal direction, the transverse path of said at least some of the laterally adjacent tiles. Connect vertical grooves so that they can communicate with each other. In this case, the tiles equipped with the traversing path are arranged above or below the wall device and / or arranged in tile rows that overlap vertically.

According to a further preferred embodiment, the tile is provided with a swiveling element, the swirling element generating a vortex in the protective gas flowing between the boiler wall and the protective lining, whereby the tile and Increases heat transfer to and from the boiler wall. The swivel element is preferably formed by a raised and / or recessed area of the tile facing the boiler wall.

  The protective gas or air discharged from the fire wall is preferably returned into the fire wall and / or supplied into the incineration plant as the first gas or air and / or as the second gas or air. The

  In the following, the fire wall according to the present invention will be described in more detail by means of an exemplary embodiment with reference to the accompanying drawings.

It is the figure which looked at the fire wall of the 1st example embodiment concerning the present invention from the direction of protection lining. It is the II-II sectional view taken on the line of FIG. It is the III-III sectional view taken on the line of FIG. FIG. 4 is an enlarged cross-sectional view of FIG. 3. It is a figure similar to FIG. 4 which shows the kind of fire wall. FIG. 5 is a perspective view showing a specially designed tile with a protective lining. It is sectional drawing similar to FIG. 3 which shows the fire wall of the 2nd exemplary embodiment which concerns on this invention. It is the schematic of the incineration plant provided with the fire wall which concerns on this invention. It is a perspective view similar to FIG. 6 which shows one form of the tile of a protective lining. It is the figure which looked at the said tile from the direction of the arrow X of FIG. It is the XI-XI sectional view taken on the line of FIG. 10 which shows the said tile. It is the XII-XII sectional view taken on the line of FIG. 10 which shows the said tile.

  "Top", "Bottom", "Width", "Height", "Vertical (vertical)", "Horizontal", "Horizontal", "Overlapping", "Adjacent to each other" etc. The term indicating the position and direction of the slab refers to the normal direction of a practical fire wall.

  The fire wall of the first exemplary embodiment according to the present invention generally indicated by the symbol W in FIGS. 1 to 4 is a pipe wall 1 (FIGS. 2 to 4) as a boiler wall and the pipe wall. And a protective lining 2 disposed with a space in front thereof, and an intermediate space 3 is formed between the tube wall 1 and the protective lining 2. The pipe wall 1 is provided with a plurality of vertical pipes 11 in practical use, and these vertical pipes are held in a state of being spaced apart from each other by a web 12. The tube 11 and the web 12 are usually made of steel. The protective lining 2 comprises a plurality of refractory tiles 21 arranged next to each other and overlapping one above the other, the refractory tiles engaging each other by complementary shaping of the ends, in this manner , Sealed to some extent. A separation and coupling portion between the tiles 21 is indicated by reference numeral 23. The tile is, for example, a ceramic SiC tile, preferably a SiC 90 tile produced with a SiC content of about 90% and has a fire resistance of 1000 degrees or more. Each tile 21 is fixed to the tube wall 1 by, for example, four tile mounting members 22. The tile mounting member is, for example, a steel no. 310 or DIN 17440 1. Made of heat-resistant steel such as 4845. The tile mounting member 22 substantially includes a square bolt 22a welded to the web 12 and provided with an internal thread, a flat side surface 22b, and a screw 22c screwed into the square bolt 22a (FIG. 4). The tile attachment member 22 engages with an open groove 21 a that continuously extends in the vertical direction toward the inside of the tile 21, and determines a distance from the tube wall to the tile 21. In the longitudinal (vertical) direction of the protective lining 2, the tiles 21 can move to some extent to allow thermal or thermal expansion or contraction movement. The side surface of the tile 21 facing the tube wall has a shape (cylindrical channel 21c in FIG. 6) adapted to the tube 11, so that the space in the intermediate space 3 between the tube wall 1 and the protective lining 2 is provided. The width or gap width d is approximately constant over the entire wall.

  Preferably, the tiles 21 of the protective lining 2 are sealed to each other by two means. As can be seen in particular in FIGS. 3 and 7, the tile joint 23 of the protective lining 2 designed in a Z-shape is sealed by a ceramic sealing strip 23a of refractory material to be inserted and an additional grout. . The ceramic sealing strip 23a provides some flexibility but does not provide a perfect seal. The latter is accomplished by sealing the additional grout 23b.

  The fire wall W is designed as a back ventilation system. This means that the intermediate space 3 between the protective lining 2 and the boiler wall, i.e. the tube wall 11 in the first exemplary embodiment, is exposed to protective gas, typically air ventilation, during operation. It is that. The gas (or air) in the intermediate space is slightly pressurized compared to the fire chamber of the incinerator. For this reason, it is avoided that corrosive smoke gas enters the intermediate space 3 from the fire chamber through the portion where the protective lining leaks and erodes the tube wall 1.

  In order to supply the protective gas to the intermediate space 3 of the fire wall and discharge the protective gas from the intermediate space, the fire wall is provided with an inlet 31 and an outlet 32, and the inlet 31 includes one or more inlets 31. And supplied by the supply unit (FIGS. 2 and 3). The supply of protective gas or air is provided from the side of the boiler wall, and the inlet 31 penetrates the boiler wall, i.e. the tube wall 1 in this embodiment, in the region of its web 12 (Figs. 3 and 4). . The discharge port 32 (FIG. 1) penetrates the protective lining 2, and as a result, the protective gas flowing through the intermediate space 3 is discharged into the boiler.

  As another embodiment, the outlet may be arranged not on the protective lining 2 but on the boiler wall, in particular on the web 12 of the tube wall 1, in which case the protective gas is discharged to the outside by this route. (In other words, instead of the inlet 31 shown in FIG. 4, a discharge port having a protective gas flow direction opposite to the illustrated direction may be provided.) The protective gas discharged to the outside is preferably sucked into a comb box 33a (FIG. 8) arranged outside the boiler wall, and for this purpose a vacuum is formed in the comb box. Is done. In this way, the amount of exhaust gas in the boiler is not unduly increased by the protective gas so that the exhaust gas purification plant is not subjected to further loads. Furthermore, if necessary, pollutants may be analyzed for the protective gas discharged outside.

  FIG. 8 shows how the fire wall W is inserted into the incineration plant. The incineration plant generally indicated by reference numeral 100 includes a raw material charging chamber 110 and a fire chamber 120 in a known manner. The refractory wall W is arranged in the area of the firebox 120 and forms part of the wall of the firebox. The supply of the protective gas or air is brought to the lower region of the fire wall W via the comb box 33 described above. In the upper wall region, a further comb box or manifold 33a is arranged, through which the protective gas or air is discharged from the refractory wall W. The discharged protective gas or discharged air may be returned to the fire wall W via the lower comb box 33 (arrow 113) or supplied to the incineration plant 100. Supply to the incineration plant is provided in the input chamber 110 as a first gas or air (arrow 111) and / or to the lower end of the fire chamber 120 as a second gas or air (arrow 112). It may be done.

  The discharge port 32 is preferably arranged at the upper end of the refractory wall, as schematically shown in FIG. The outlet 32 may be formed in a portion of the tile joint 23 that is not sealed, or alternatively may be constituted by an opening in the web 12 of the tube wall 1 as described above. As shown in FIG. 2, the injection port 31 may be disposed in the base of the fire wall, that is, in the vicinity of the lower end of the fire wall. However, the inlets 31 may be distributed over the entire wall surface or over individual regions of the wall surface.

  A substantial feature of the present invention is that, as is apparent from FIGS. 3 and 4 in particular, a supply of protective gas or air is provided directly in the region of the continuous open groove 21a of the tile 21. In FIG. 4, the supplied air is represented by an arrow L. The inlet 31 is disposed in the web 12 in the area of the open groove 21a. The supplied gas or air first enters the open groove 21a, and in this process there is no great flow resistance due to the larger cross section and it can spread over the entire refractory wall. Thereby, the intermediate space 3 between the boiler wall, that is, the tube wall 1 in the present embodiment and the protective lining 2 suspended forward can be greatly reduced, and the actual gap width d (FIG. 4) is It can only be 1-5 mm, preferably 1-3 mm. The tube wall 1 can also contact the tiles 21 without being damaged in some areas. By using the groove 21a as a path of protective gas or air in the fire wall and the reduced distance d between the tube wall 1 and the protective lining 2, a relatively small amount of gas or air is sufficient. The pressure loss is extremely small. Compared to the pressure inside the boiler, the required pressure can be reduced to 1-10 mbar, preferably 1-5 mbar. This in turn creates significant energy savings in actual operation. Furthermore, the distance between the tube wall and the protective lining is reduced, so that the heat conduction is substantially increased.

  A further improvement in the distribution of protective gas or air within the fire wall according to an advantageous further development of the invention is that several horizontal tile rows of the protective lining at a given longitudinal interval, for example every 2-4 m, Compared to the rest of the tiles, they are arranged so that the distance from the tube wall is slightly larger, thereby forming a horizontal transverse path, through which the air extends over the entire width of the refractory wall. It can spread over.

  In addition or alternatively, as shown in FIGS. 5 and 6, in a particularly advantageous further configuration of the invention, a transverse path extending substantially horizontally may be formed. This is particularly important when the refractory wall is equipped with a device that blocks vertical grooves, such as a burner or window, in actual operation, in which case the wall portion located above the device, or In another embodiment in which protective gas or air is supplied from the top, protective gas or air cannot be supplied directly to the wall part located below the device. FIG. 5 shows the details of the wall with the device 40. According to FIG. 5, it is clear that the groove 21 a is blocked in the device 40. In order to be able to supply air to the wall portion or tile 21 located above the device 40, a tile path 21b is provided in the tile 21 of the tile row located directly above the device, the route being the tile row. The vertical grooves 21a in the tile 21 are connected so as to be able to communicate with each other. In this embodiment, as shown by the unsigned arrows in FIG. 5, the protective gas or air flows out of the laterally adjacent grooves 21a that are not blocked by the crossings, and the grooves of the tiles 21 located above the device 40. It can flow into 21a.

  FIG. 6 shows the tile 21 in which the transverse path 21b is formed. As is apparent from FIG. 6, the crossing path 21b is open on both sides of the tile 21, so that the crossing paths of adjacent tiles form a continuous flow path.

  The transverse path 21b need not extend through the entire tile row located above the device 40. In fact, if tiles adjacent to at least one side of the tile row are located laterally outside the device so that they can communicate, the tiles located above the device are connected on at least one side. It is sufficient, but it is preferable to connect on both sides. Even if the vertical protective gas or air flow is not obstructed by any device, it is possible to arrange tile rows with transverse paths at predetermined intervals or equip all tiles with transverse paths. It can be advantageous to obtain a better flow distribution.

  According to a further important feature of the present invention, as shown in FIGS. 9-12 in a mere exemplary manner, the swivel element is arranged in a protective gas or air flow path, thereby providing a protective lining 2 and The heat conduction with the tube wall 1 can be increased.

  In one embodiment, the swivel element can be composed of a curved rib 21d raised in the region of the cylindrical channel 21c of the tile 21. Alternatively or additionally, the swivel element may be constituted by a recess 21e in the area of the protective gas or air flow path. Finally, the turning element may be constituted by a pin-like member 21f protruding into the open groove 21a.

  As already mentioned, the supplied protective gas or air is provided via one or more supply parts 33, preferably configured as a comb box. The blower necessary for guiding the air is driven by, for example, a frequency-controlled motor, and pressurization in the groove 21a measured at one or a plurality of positions is used for controlling the blower. In this embodiment, energy requirements can be optimized or minimized.

  As already described at the beginning, the boiler wall of the fireproof wall according to the present invention does not necessarily have to be designed as a tube wall, and may be a normal metal wall, for example. FIG. 7 schematically shows a second exemplary embodiment in which the boiler wall is designed as a flat metal wall 1 'as described above. Also in this exemplary embodiment, the supply of air into the groove 21a of the tile 21 and the reduction of the gap width of the intermediate space 3 achieved thereby provide the above-mentioned effect.

1: tube wall (boiler wall), 1 ′: metal wall (boiler wall), 2: protective lining, 3: intermediate space, 11: tube, 12: web, 21: fireproof tile, 21a: open groove, 21b: Crossing path, 21c: cylindrical channel, 21d, 21e, 21f: swivel element, 22: tile mounting member, 31: inlet, 32: exhaust port, 33: supply section, 100: incineration plant, 110: raw material input chamber 120: Firebox.

Claims (15)

A tube wall (1) comprising a tube (11) connected by a web (12) ;
Are arranged with a space from the tube wall, and a plurality of refractory secured to the tube wall, respectively via at least one tile mounting member (22) while being arranged so as to overlap vertically and adjoin each other A refractory protective lining (2) having a conductive tile (21),
An intermediate space (3) is at least partially interposed between the tube wall (1) and the protective lining (2);
A back ventilated fireproof wall further comprising gas supply means (31) for supplying protective gas into the intermediate space (3) between the tube wall (1) and the protective lining (2). And
The tile (21)
A groove (21a) that extends continuously in a substantially vertical direction, opens toward the tube wall (1) , has a cross section that extends into the interior of the tile (21), and engages with the tile mounting member (22). )
The gas supply means (31) supplies the protective gas into the groove (21a) and / or supplies the protective gas into a region facing the groove (21a) in the intermediate space (3) . Fireproof wall.   2. The fire wall according to claim 1, wherein the grooves (21 a) between the tiles (21) adjacent in the vertical direction are in a straight line and are connected so as to be able to communicate with each other. The refractory wall according to claim 1 or 2, wherein the gas supply means includes an inlet (31) arranged in a region of the groove (21a ) in the pipe wall (1) . The said injection port (31) is arrange | positioned in the lower area | region of the said tube wall (1) , or is distribute | distributed over the whole wall surface of the said tube wall . Fire wall. The fire wall according to claim 3 or 4 , characterized in that the inlet (31) is arranged in the region of the web (12).   The fire wall according to any one of claims 1 to 5, wherein a gap width (d) of the intermediate space (3) is 5 mm or less.   The fire wall according to any one of claims 1 to 6, further comprising means (32) for discharging the protective gas from the intermediate space (3) and the groove (21a). The means for discharging the protective gas is:
The fire wall according to claim 7, further comprising a discharge port (32) disposed at the top of the fire wall and penetrating through the protective lining (2) or the pipe wall (1) .   Between the refractory tiles (21), a ceramic sealing strip (23a) of inserted refractory material and a tile joint (23) sealed by an additional grout (23b) are interposed. The fireproof wall according to any one of claims 1 to 8. The tile mounting member (22)
A bolt (22a) fixed to the tube wall (1) and provided with an internal thread;
A flat tile support surface (22b);
A screw (22c) screwed into the bolt (22a),
The fire wall according to any one of claims 1 to 9, wherein a distance from the pipe wall (1) to the tile (21) can be changed by the screw. The tiles (21) of at least one horizontal tile row are arranged so that the spacing from the tube wall (1) is slightly larger than the remaining tiles, so that the protective gas is The fire wall according to any one of claims 1 to 10, characterized in that it forms a transverse path that allows it to extend over the entire width of the fire wall. On at least some laterally adjacent tiles (21),
There is provided a continuous transverse path (21b) extending in a substantially horizontal direction and connecting the vertical grooves (21a) of said at least some laterally adjacent tiles (21) in a mutually communicable manner. The fireproof wall according to any one of claims 1 to 11, wherein: A fire wall according to claim 12, characterized in that the tile (21) equipped with a transverse path (21b) is arranged above or below the device (40) provided on the fire wall. A fire wall according to claim 12 or 13, characterized in that the tiles (21) equipped with a transverse path (21b) are arranged on a plurality of horizontal tile rows spaced from each other . As the swivel element for the protective gas flowing between the pipe wall (1) and the protective lining (2), the curved rib (21d) raised from the pipe wall side surface of the tile (21), the tile Either the depression (21e) provided on the tube wall side surface in (21) or the pin-like member (21f) provided on the tile (21) so as to protrude into the groove (21a) The fireproof wall according to any one of claims 1 to 14, characterized in that a swiveling element composed of is provided.

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